Chromium-resistant PGPB: Growth stimulatory impact on Vigna radiata L. under chromium stress

摘要

Five already identified chromium-resistant bacterial strains exhibiting auxin biosyntheticpotential (Bacillus sp. AMP2, Halomonas sp. AST, Arthrobacter mysorens AHA, Kushneria avicenniaeAHT, Halomonas venusta APA) were used in the present study. Bacterial strains were used to inoculateseeds of Vigna radiata var. NM-2006 under chromium stress and impact of these strains on the growthof Vigna radiata was studied in the absence and presence of various concentrations (0-100μg/ml) ofCr-stress by recording various growth parameters of inoculated and non-inoculated seedlings. Most ofthe isolates improved plant growth under chromium stress by exerting beneficial impact on shootlength, root length and fresh weight of the inoculated treatments as compared to the growth observed innon-inoculated treatments under chromium stress. Similarly considerable improvement in thebiochemical parameters i.e., auxin content and photosynthetic pigments of the inoculated treatmentswas observed in comparison with the non-inoculated treatments under chromium stress. Among theisolates, Halomonas venusta APA and Arthrobacter mysorens AHA were found to be most effectiveisolates with phytostimulatory impact on the growth of Vigna radiata L.